Device for horizontally aligning expansion corrugated pipes, and pipe aligning welding method

The invention discloses a device for horizontally aligning expansion corrugated pipes, and a pipe aligning welding method. The device comprises two clamping mechanisms which are arranged coaxially, horizontally and symmetrically and are used for clamping two horizontal expansion corrugated pipes for corrugated pipe welding, and a driving device drives the clamping mechanisms to rotate through a drive support device. Each clamping mechanism comprises two symmetrical transmission wheels which clamp the expansion corrugated pipes, and a circle of rack which is matched with a driving gear is arranged outside each main transmission wheel; and the interior of each main transmission wheel has an 8-shaped structure which is mutually matched with the section of each expansion corrugated pipe. The device can clamp and rotate two horizontal corrugated pipes so as to keep the welding position always in a flat welding position. The device is used for horizontal pipe aligning operation of the expansion corrugated pipes, th